William R Pritchard Veterinary Medical Teaching Hospital, University of California-Davis, Davis, CA, USA.
Department of Surgical and Radiological Sciences, School of Veterinary Medicine, University of California-Davis, Davis, CA, USA.
J Feline Med Surg. 2022 Apr;24(4):277-283. doi: 10.1177/1098612X211013736. Epub 2021 May 10.
Feline arterial thromboembolism (ATE), an often devastating outcome, was recently shown to affect 11.3% of cats with hypertrophic cardiomyopathy over 10 years. Current American College of Veterinary Internal Medicine guidelines recommend the use of clopidogrel in cats at risk for ATE, with addition of a factor Xa inhibitor in very high risk or post-ATE cases. To date, no studies have examined the safety or efficacy of this combined antithrombotic therapy. This retrospective case series aimed to assess the frequency and type of adverse events that occurred in cats prescribed dual clopidogrel and rivaroxaban therapy. Secondary aims were to evaluate indications for dual therapy and clinical outcome.
The study included 32 cats prescribed clopidogrel (18.75 mg PO q24h) and rivaroxaban (2.5 mg PO q24h) on an outpatient basis over a 5-year period.
Cats were prescribed dual therapy for at least one of the following: ATE event (n = 18), presence of an intracardiac thrombi (n = 17) or presence of spontaneous echocardiographic contrast (SEC) (n = 16). Five cats experienced adverse effects that could be attributed to medications, a median of 13 days from initiation (epistaxis, hematemesis, hematochezia or hematuria). No cat required hospitalization as a result of these events. Median survival time from onset of therapy was 257 days (interquartile range [IQR] = 38-497) for all cats, 502 days (IQR = 171-663) for ATE cats, 725 days (IQR = 133-856) for cats with an ATE to two or more limbs and 301 days (IQR = 221-431) for cats with only one limb affected. Recurrence rate of ATE while on dual therapy was 16.7%; no cat newly developed an ATE while on dual therapy.
Dual antithrombotic therapy with clopidogrel and rivaroxaban resulted in a low reported incidence of adverse events. Cats placed on dual therapy for an ATE event experienced a low rate of recurrence and effective thromboprophylaxis was achieved in cats with intracardiac thrombi or SEC.
猫动脉血栓栓塞症（ATE）是一种常导致严重后果的疾病，最近的研究表明，在 10 年内，11.3%患有肥厚型心肌病的猫患有 ATE。目前，美国兽医内科学会的指南建议对有发生 ATE 风险的猫使用氯吡格雷，并在极高风险或 ATE 后使用因子 Xa 抑制剂。迄今为止，尚无研究检查这种联合抗血栓治疗的安全性或疗效。本回顾性病例系列旨在评估接受氯吡格雷和利伐沙班联合治疗的猫发生不良事件的频率和类型。次要目标是评估联合治疗的适应证和临床结果。
本研究纳入了在过去 5 年内因 ATE 事件（n=18）、存在心内血栓（n=17）或自发性超声心动图对比（SEC）（n=16）而接受氯吡格雷（18.75mg PO q24h）和利伐沙班（2.5mg PO q24h）的门诊治疗的 32 只猫。
至少有一只猫因以下原因接受了双重治疗：ATE 事件（n=18）、存在心内血栓（n=17）或存在 SEC（n=16）。有 5 只猫出现了可能与药物相关的不良事件，从开始治疗到出现不良事件的中位时间为 13 天（鼻出血、呕血、血便或血尿）。没有猫因这些事件需要住院治疗。所有猫的中位生存时间从开始治疗起为 257 天（四分位距 [IQR]=38-497），ATE 猫为 502 天（IQR=171-663），ATE 累及两条或以上肢体的猫为 725 天（IQR=133-856），仅一条肢体受累的猫为 301 天（IQR=221-431）。在双重治疗期间，ATE 的复发率为 16.7%；没有猫在双重治疗期间新发生 ATE。
氯吡格雷和利伐沙班联合抗血栓治疗的不良反应发生率较低。接受 ATE 事件双重治疗的猫复发率较低，在存在心内血栓或 SEC 的猫中实现了有效的血栓预防。
